I am currently trying to build an experimental lander prototype using model rocket engines. due to my design, I am going to need several motors that are about 10 centimeters apart so the risk of flipping is high if not all motors activate at the same time.
How exactly many motors is "several"?
What is the overall shape and size of your model?
What motors are you planning to use, how how will the contraption be descending back to the ground (under chute? gliding?)
All things being equal, black-powder (BP) are easiest to ignite "nearly" simultaneously.
Whether or not "nearly" will be good enough for your application, is hard to determine, with the information shared thus far.
I have looked for information regarding ignition variation between the same models but I haven't been able to find anything. I was wondering if anyone had any advice or data for how much variation in the ignition I should expect.
It all depends on what types of rocket motors you are suing, how many rocket motors, what type of ignitors you are using, and what type of ignition system and ignition wires you plan on using.
If you want a deterministic answer, please specify all five (5) with maximum specificity.
Without that, my best guess is that BP-motors will be your best guess, and just might give you the desired outcome 2 out of 3 times.
HTH,
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